Re: tkinter file dialog pattern matching

Hi,

On Sat, 22 Aug 2015 21:04:24 +0100
Pawel Mosakowski <[email protected]> wrote:

> Hi,
> 
> I've found this little gem in the Tk docs
> https://www.tcl.tk/man/tcl8.4/TkCmd/getOpenFile.htm#M13
> From what I see "file patterns" in the file dialog are not "regex
> patterns" and do not support special characters. Only things that work
> are:
> 1) * - any extension
> 2) "" - files without extension
> 3) literal extension without wildcard chars
> Unfortunately it looks like there is no simple way to filter out hidden
> files.

actually the unix tk file dialog has an an (however undocumented) feature
to hide hidden elements and display even a button that allows to toggle
between hidden elements on/off, however we need to do a little tcl to get
to this. Since the feature is not documented anywhere it might also be a
good idea to wrap this into a try...except. See this little code snippet:

#############################################
from Tkinter import *
import tkFileDialog as tkfd

root = Tk()

try:
    # call a dummy dialog with an impossible option to initialize the file
    # dialog without really getting a dialog window; this will throw a
    # TclError, so we need a try...except :
    try:
        root.tk.call('tk_getOpenFile', '-foobarbaz')
    except TclError:
        pass
    # now set the magic variables accordingly
    root.tk.call('set', '::tk::dialog::file::showHiddenBtn', '1')
    root.tk.call('set', '::tk::dialog::file::showHiddenVar', '0')
except:
    pass

# a simple callback for testing:
def openfile(event):
    fname = tkfd.askopenfilename()
    print(fname)
root.bind('<Control-o>', openfile)

root.mainloop()
#############################################

Best regards

Michael

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